1. Field of the Invention
The invention relates to operating mechanism for cameras, particularly "throw away" cameras which are discarded after a single use. The mechanism is of simple, inexpensive construction, yet provides reliable shutter actuation, double exposure prevention, film winding with automatic winder lock-up at each film frame, and exposure counting.
2. Description of the Prior Art
U.S. Pat. No. 4,057,814, issued Nov. 8, 1977 discloses an electrically operated shutter in a camera having a rotatable winding knob which moves the film in the camera and cocks a shutter. Rotation of the winding knob displaces a slide between an initial position to which it is urged by a spring, and an end position. In its initial position, the slide blocks a shutter release button against actuation. Movement of the slide to its end position releases the button for actuation. Coaction between the release button and the slide releases the slide for spring biased movement to its initial position upon actuation of the release button, such movement operating electric contact means to operate the camera shutter.
From a study of the following specification and appended drawings it will be seen that the present invention differs broadly in construction and operation from the above discussed patent. While the present invention also uses a slide, the slide actuates the shutter by spring action upon depression of the shutter release button by the user. The slide is blocked against shutter actuating movement from its cocked position by contact with the periphery of a film winding gear wheel, the latter being moved to an unblocking position by depression of the shutter release button. Rotation of the gear wheel rotates a second gear wheel which has a raised cam surface lying within an opening in the slide and operable upon rotation of the first gear wheel to move the slide against the spring pressure back to cocked position. The first gear wheel carries the shutter release button and is spring urged to the slide blocking position. The first gear wheel also operates the film transport mechanism. Lugs on the second gear wheel and slide cooperate to limit rotation of the gears to an amount which moves the film by one frame. There is also a counter mechanism operated by one of the gear wheels. In the preferred embodiment disclosed, the construction is entirely mechanical.
From the foregoing description it should be clear that the present invention is new and unobvious over the patented construction.